Soil and water analysis for research, advisory services, formulation of recommendations, and designing appropriate soil management and water management practices is employed for various applications. Soil and water analysis may be conducted for estimating the availability of plant nutrients, geotechnical and ecological investigations, analyzing chemical composition of soil, determining soil moisture content, and measurement of various parameters in water bodies (e.g., pH, dissolved oxygen, oxidation-reduction potential, conductivity or salinity, temperature, turbidity, and dissolved ions such as fluoride, carbide, nitrates, lead, iodine, etc.)
Soil study is often conducted for analyzing soil composition for agronomic purposes. For many years, soil analysis has been used as an aid in assessing soil fertility and plant nutrient management. The soil analysis reports may provide information to set nutrient application targets, which are used to calculate manure and fertilizer application rates. Regular analysis from field sampling allows monitoring and detection of changes in the soil parameters over time, such as nutrients, pH, and salinity. Soil testing, in particular, is also important in monitoring the various types of land degradation and the choice of measures for land improvement. Development of effective and efficient analytical services of soil, water, plant, and fertilizers is thus important for increasing and sustaining land productivity, as well as crop and food production.
A variety of sensors, such as electromagnetic, optical, mechanical, electrochemical, airflow, and acoustic sensors, are conventionally available that can measure various parameters in soil and water. For instance, soil moisture sensors measure the volumetric water content in soil. Certain sensor probes measure temperature, pH, and electrical conductivity. Metal probes may measure the concentration of various elements, such as nitrogen, phosphorous, potassium, etc., in the soil and water.
Since one sensor can typically measure only one parameter, it is difficult to measure more than a single parameter at a time. Moreover, if two or more sensors are used to measure two different parameters, the quantity of the parameters at different levels cannot be ascertained. Accordingly, an improved sensor architecture and device that can analyze different parameters at varying depth may be beneficial.